CD4 and cancer: Given that CD25+ Tregs are an independent risk factor for a poor prognosis in patients with CRC, we used CD4 and CD25 as Treg markers instead of CD4 and FOXP3.[18] By the 7th edition of the American Joint Committee on Cancer (AJCC) cancer staging system, we categorized tumor tissues with a grade <T3 as low‐grade tumors and those with a grade ≥T3 as high‐grade tumors.